The present invention relates to a method for use with a damper. In a more specific aspect, this invention relates to a method for controlling the damping force of a damper.
As used in this application, the term xe2x80x9cdamperxe2x80x9d refers to an apparatus having a movable object (such as a piston, rotor or rod) within a fluid which is subject to changes in viscosity, and the term xe2x80x9cdamping forcexe2x80x9d refers to the resistance to movement of the movable object. More specifically, the term xe2x80x9cdamperxe2x80x9d includes conventional piston-type shock absorbers, rotary shock absorbers and any other apparatus in which movement or motion of the movable object is dampened (i.e., resisted or reduced) by the viscosity of the fluid.
In many instances, this invention will be described in detail with specific reference to conventional piston-type shock absorbers. However, this invention will be understood as applicable to other types of dampers, such as rotary shock absorbers.
In a conventional type of shock absorber, a piston is carried on the end of a reciprocating rod that extends from the shock absorber cylinder and is connected to one part of a movable mass, such as the chassis of a motor vehicle, while the body of the shock absorber is connected to the vehicle running gear. Alternatively, these mountings can be reversed for inverted mounting of the shock absorber.
Alternatively, the damper can be a rotary shock absorber which normally has a lever extending from the shock absorber body and connected to one part of a movable mass, such as the chassis of a motor vehicle or the vehicle running gear. The connection is normally by an articulated line.
However, in many situations such as auto races, the driver needs greater control over the operation of a shock absorber than is possible with conventional or rotary shock absorbers. Greater control is essential in handling a fast-moving car on a race track to achieve safety and a xe2x80x9cwinning edgexe2x80x9d. In a shock absorber, this translates into greater control over the damping force of the shock absorber.
Consequently, there is a need in this industry for a method which will provide greater control over the damping force of a shock absorber.
Briefly described, the present invention provides a method especially adapted for controlling the damping force of a magneto-rheological shock absorber. As used in this application, the term xe2x80x9cmagneto-rheological shock absorberxe2x80x9d (or M-R shock absorber) refers to a shock absorber in which a magneto-rheological fluid (or M-R fluid) is used in place of an oil. A M-R shock absorber has an electromagnetic coil which is designed to produce a magnetic field (i.e., by magnetizing the M-R fluid) as such fluid flows through one or more passageways in the shock absorber and dampens (or resists) motion of the piston, rotor, rod or other movable object in the shock absorber.
The viscosity of the M-R fluid will change in response to the strength of the magnetic field. Further, the strength of the magnetic field will vary depending upon an electrical current or voltage which is provided to the electromagnetic coil in the M-R shock absorber.
More specifically, as the strength of the magnetic field increases, the viscosity of the M-R fluid increases, which results in an increase in the damping force of the M-R shock absorber. Conversely, as the strength ofthe magnetic field decreases, the viscosity of the M-R fluid decreases, which results in a decrease in the damping force of the M-R shock absorber. The increase or decrease in the damping force of the M-R shock absorber provides the driver with greater control over the car being operated by such driver.
Accordingly, an object of this invention is to provide a method for use with a damper.
Another object of this invention is to provide a method for controlling the damping force of a damper.
Another object of this invention is to provide a method for use with a shock absorber.
Another object of this invention is to provide a method for controlling the damping force of a shock absorber.
Another object of this invention is to provide a method which utilizes and deals with the principle of magnetic hysteresis.
Still another object of this invention is to provide a method which will provide the driver with greater control over the car being operated by such driver.
Still another object of this invention is to provide a method which will provide the driver of a race car with greater control over the car at high speeds and various track conditions in racing situations.
Still another object of this invention is to provide a method which will provide a driver with greater control over the handling of a vehicle while traversing varying road conditions or varying loads on the vehicle.
These and other objects, features and advantages of this invention will become apparent from the following drawing and detailed description.